Recommended dietary intakes (RDI) of folate in humans

Harmful effect of megadoses of vitamins: electroencephalogram abnormalities and seizures induced by intravenous folate in drug-treated epileptics.

From studies in lower animals, it is believed that deficiency of folic acid during the intrauterine period may lead to an infant’s being born mentally retarded.(1) The use of antimetabolites to folic acid is known to produce abortion in woman and also to produce a fetus with central nervous system and other deformities.(2,3) Work by Arakawa’s group(4) in Japan suggests that congenital enzyme defects in folate metabolism result in infants born with mental retardation, dilation of the cerebral ventricles, and intracerebral calcification. There is as yet no clear evidence that folate deficiency in adults produces histologically demonstrable damage to the central nervous system. However, folate deficiency in adults is associated with irritability and forgetfulness.(5) Furthermore, it has been suggested, most recently by Reynolds,(6) that anticonvulsants act in part by interfering with folate metabolism and that the supplying of folic acid increases fit frequency in patients whose convulsions would otherwise have been better controlled by anticonvulsant medication. This chapter will review what is known about the mechanisms whereby deficiency of folic acid may produce these alleged effects.

Cuttner J

Papers

Sequence of recovery from multiple manifestations of frolic acid deficiency.